Reliable data for Mexican, Cuban, and Puerto Rican migrant subpopulations first became available in 1979 when the National Center for Health Statistics expanded its coding for selected places of birth. Since most states with large Hispanic populations now code Hispanic identifiers on death records, mortality data are also available for Hispanics in these areas, regardless of generation in the United States. These new data have made possible comparisons of mortality rates by age, sex, and leading cause of death among Hispanic subpopulations and Anglos. The proposed research, a series of major follow-up studies of the mortality of specific Hispanic subpopulations, is intended to generate new knowledge concerning observed mortality patterns with special focus on the potential role of environmental and endogenous factors in specific causes of death. In the first study mortality data for migrants will be compared with similar data for the countries of origin to determine how migrants differ from non-migrants and how migrants differ from their U.S.-born children. The second study will seek explanations for geographic variations in mortality observed within the same Hispanic subpopulations. Mortality rates for Mexican Americans, e.g., are higher in Texas than in California and those for Puerto Ricans are higher in New York City than outside the city. The third study will examine the generally high mortality among Hispanic adolescents and young adults, particularly males, which is largely due to violent deaths. The final study will consider social and environmental factors as possible causes for the relatively low death rates for elderly Hispanic subpopulations as compared with those observed for non-Hispanics. The aged Hispanic group in the U.S., despite their disadvantaged socioeconomic status, exhibit much lower death rates from heart disease and cancer which account for two thirds of all deaths among persons aged 45 and over. Demographic data on social and economic characteristics will be obtained from the 1980 census public use samples. Health survey data, including the Hispanic HANES and the Puerto Rican Master Sample Survey data will be used to determine major risk factors associated with specific illnesses among the three Hispanic populations. The objectives of the study are to determine environmental, cultural, and biological factors that contribute to cause-specific differences in mortality 1) among Hispanic subpopulations and the Anglo population, 2) between Hispanic subpopulations in different locales, and 3) between different generations among Hispanics.